CephamycinsCephalosporinsbeta-LactamasesCephalosporin ResistanceCefoxitinMicrobial Sensitivity Testsbeta-LactamsAnti-Bacterial AgentsKlebsiella pneumoniaeIsoelectric FocusingCephaloridinePlasmidsCefotaximeCephalexinPenicillinsCephalosporinaseDrug Resistance, MicrobialBacteriaCeftriaxoneAntibiotic ProphylaxisCefiximeCephalothinDrug Resistance, BacterialEnterobacteriaceaeCefmenoximebeta-Lactam ResistanceCefazolinCeftazidimeCephradineGram-Negative BacteriaCefotiamBacterial InfectionsEnterobacterCeftizoximeAztreonamPenicillin ResistanceEscherichia coliPenicillinaseAmpicillinAminoglycosidesDrug Resistance, Multiple, BacterialEnterobacteriaceae InfectionsDrug UtilizationCefamandolePenicillin GKlebsiellaCarbapenemsStreptomycesGram-Positive BacteriaLactamsCefoperazoneCefaclorCross InfectionCefuroximeKlebsiella InfectionsMoxalactamChemistryBacterial ProteinsChemical PhenomenaCefmetazoleCloxacillinCefadroxilPseudomonas aeruginosaGram-Negative Bacterial InfectionsStaphylococcus aureusImipenemThienamycinsGentamicinsEnterobacter cloacaePenicillanic AcidClavulanic AcidAntibiotics, AntineoplasticDNA, BacterialPenicillin-Binding ProteinsStructure-Activity RelationshipCefotetanAnti-Infective AgentsKanamycinEscherichia coli InfectionsNeisseria gonorrhoeaeGonorrheaPenicillin VCephaloglycinVancomycinCefsulodinStreptococcus pneumoniaePiperacillinMonobactamsCefatrizineErythromycinFluoroquinolonesProteusBacteremiaConjugation, GeneticHydrolysisCiprofloxacinCulture Media